JPH08192709A - Air bag device - Google Patents

Abstract

PURPOSE: To provide an air bag device having a switch being excellent in operating feeling. CONSTITUTION: A folded up air bag is covered with a cover body 34 being elastically deformable. A cover body 34 is provided with a brittle tear line 44 breaking down during the expansion of the air-bag and a pair of a front and a rear door piece part 48, 48 which develop at the time of breakdown of the tear line 44 to compose the protruding port of the air-bag. Film-shaped switches 32, 33 are attached along the back side of each of door piece parts 48, 48 of the cover body 34. A switch part 57 to close at the time of deformation is provided in the film-shaped switches 32, 33. The switch part 57 of the film- shaped switch 33 on a rear side is arranged across the central break line 46 of the tear line 44 so that its switch part 57 may be piled up on the switch part 57 of the film-shaped switch 32 on a front side. Thus even in the case where a part of the central break line 46 of the cover body 34 is pushingly moved, the switch part 57 can be easily closed for improving the operating feeling of the switch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device having a switch and a cover body covering the airbag.

[0002]

2. Description of the Related Art Conventionally, for example, a steering wheel described in Japanese Utility Model Laid-Open No. 4-28170 is known. And on the boss part of this steering wheel,
An airbag device including an inflator that injects gas and an airbag that inflates and deploys with the gas is attached. Further, such an airbag device is provided with a base plate for mounting the airbag and the inflator, and the base plate is
A cover body is attached to cover the folded airbag. A groove-shaped tear line having, for example, a substantially H-shaped plane is formed on the cover body, and a pair of door pieces is formed in a state of being divided by the tear line.
Therefore, in the event of a vehicle collision, the inflator injects gas to inflate the airbag, and the pressure of this inflation causes the cover body to tear along the tear line and to deploy the door pieces forward and backward. Form the mouth of the bag. Then, the airbag is projected through the projecting port, and the airbag is inflated and deployed in front of the occupant.

Also, in this airbag device, film-like switches are attached to the back side of each door piece of the cover body, and these switches are connected to a horn device provided on the vehicle body side. . Further, in this airbag device, a receiving plate is provided between the switch and the airbag so that an uneven load is not applied from the airbag to the switch. Therefore, by pushing the cover body, the film-like switch is closed and the horn device provided on the vehicle body side is operated.

[0004]

However, in the above-mentioned conventional structure, when the operator operates the horn switch, the operator pushes the portion of the cover body on the tear line and the portion other than the tear line is pushed. In some cases, the amount of operation required to close the switch changes, which makes it difficult to improve the operational feeling of the switch.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an airbag device provided with a switch having a good operation feeling.

[0006]

An airbag device according to claim 1, wherein the airbag is inflated by the inflow of gas, a fragile rupture portion which covers the airbag and ruptures when the airbag is inflated, and the rupture. Membrane switch provided with an elastically deformable cover body provided with a door piece portion that expands when the portion breaks, and a switch portion that is attached along the back surface side of the door piece portion of the cover body and that is closed when deformed With and
At least a part of the switch portion of the membrane switch is disposed on the back surface side of the break portion.

The airbag device according to a second aspect of the invention is expanded by the airbag which is inflated by the inflow of gas, the fragile breakage portion which covers the airbag and is broken when the airbag is inflated, and the fractured portion. An elastically deformable cover body provided with a plurality of door piece portions, and a plurality of film-shaped switches provided with a switch portion attached along the back surface side of each door piece portion and closed at the time of deformation, The switch portion of each of the film switches is arranged such that at least some of them overlap each other.

[0008]

In the airbag device according to the present invention, by pushing the elastically deformable cover body, the switch portion of the membrane switch is deformed together with the cover body, and the switch portion of the membrane switch is closed. It Since at least a part of the switch portion of the film-shaped switch attached along the back surface side of the door piece portion of the cover body is arranged so as to be located on the back surface side of the break portion, the break portion portion of the cover body is When pushed, the switch portion is easily closed, as in the case where the portion of the cover body other than the fractured portion is pushed. When the airbag is inflated, the pressure of the inflation of the airbag causes the cover body to tear along the fragile breaking portion, the door piece portion is deployed, and the protruding port of the airbag is formed.

In the airbag device according to the second aspect, by pushing the elastically deformable cover body, the switch portion of the membrane switch is deformed together with the cover body, and the switch portion of the membrane switch is closed. It Since the plurality of film switches attached along the back surface side of each door piece of the cover body are arranged in a state where at least some of the switch sections overlap each other, the broken section of the cover body is Including, the feeling of operation when pushing each part of the cover body is made uniform. When the airbag is inflated, the pressure of the inflation of the airbag causes the cover body to tear along the fragile break portion,
Each door piece expands to form a protruding port of the airbag.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of an embodiment of the airbag device of the present invention will be described below with reference to the drawings.

In FIG. 2, reference numeral 11 denotes a steering wheel of an automobile. The steering wheel 11 includes a steering wheel body 12 and a steering wheel body.
It is composed of an airbag device 14 mounted on the upper side of the occupant 12, and the like.

The steering wheel body 12 is
The rim portion 15 has an annular shape, a boss portion 16 located inside the rim portion 15, and a plurality of spoke portions 17 connecting the rim portion 15 and the boss portion 16. Further, on the lower side of the steering wheel main body 12 that is the vehicle body side, a metal-made substantially cylindrical boss that is fitted to a steering shaft (not shown) is arranged, and this boss is made of a metal plate or the like. The boss plate is fixed by welding. Also, on this boss plate, the spoke part
The core metal of 17 is connected, and the core metal of the rim portion 15 is connected to the core metal of the spoke portion 17. And these rim parts 15
On the outer peripheral portion of the core metal and the outer peripheral portion of the spoke portion 17 on the rim portion 15 side of the core metal, a skin portion made of a soft synthetic resin,
18 are formed. Further, the lower side of the boss 16 is covered with a resin lower cover.

Further, as shown in FIG. 3, the airbag device 14 is provided with a metal base plate 21 as a member to be attached, and the base plate 21 is attached to the boss plate of the steering wheel body 12 via a bracket or the like. It is like this. And this base plate
21 includes an upper plate portion 22 having a substantially rectangular shape in plan view and the upper plate portion 22.
And a peripheral wall portion 23 extending downward from the peripheral edge portion of the. A circular hole-shaped inflator mounting hole 22a is formed in the upper plate portion 22, and the inflator is fitted into the inflator mounting hole 22a to inject gas.
24 is installed and this inflator 24
A bag-shaped airbag 25 is attached in a folded state so as to cover the upper side of the. The airbag 25 has an annular retainer 26, the vicinity of the opening 25a of which is pressed against the upper surface of the base plate 21, and the bolt 27 protruding downward from the retainer 26 is attached to the airbag 25 and the base plate. The airbag 25 is fixed to the base plate 21 together with the inflator 24 by inserting the inflator 24 and the flange portion 24a of the inflator 24 and screwing a nut 28 from the lower surface of the flange portion 24a.

Further, the folded airbag 25 is covered on the surface side by a wrapping member 31 made of paper or polyester film, and the base plate 21 covers the airbag 25 so as to cover the airbag 25. A pair of front and rear membrane switches that make up the
The cover body 34 to which is attached is attached.

As shown in FIGS. 1 to 4, the cover body 34 is integrally formed of a synthetic resin, for example, a thermoplastic elastomer.
An upper plate portion 36 that covers a part of the boss portion 16 and the spoke portion 17 of
And a mounting wall portion 37 having a substantially rectangular tube shape and protruding downward from the back surface of the upper plate portion 36. Also, this mounting wall
A plurality of engaging protrusions 37a are provided on the inner side of the protrusion 37, and a square-shaped rivet through hole 37b is formed. The cover body 34 has the mounting wall portion 37 fitted to the outer side of the peripheral wall portion 23 of the base plate 21, the engaging projections 37a engaged with the engaging holes 23a formed in the peripheral wall portion 23, and the peripheral wall portion. The mounting wall portion 37 is fixed to the peripheral wall portion 23 and fixed to the base plate 21 by a rivet 38 that inserts a through hole 23b formed in the portion 23 and a rivet through hole 37b communicating with the through hole 23b. It should be noted that a plurality of reinforcing ribs 39 are formed on the back surface side of the upper plate portion 36 and located outside the mounting wall portion 37.

Further, the surface side of the upper plate portion 36 of the cover body 34 is formed by combining a complicated curved surface (third curved surface) curved in the front-rear direction and both side directions in order to improve the appearance. There is. Further, on the surface side of the upper plate portion 36, a horn switch operation portion 41 is formed so as to be elastically deformable in the vertical direction, and an annular groove 42 indicating the operation range is formed around the operation portion 41. At the same time, a central recessed groove 43 for partitioning the operation portion 41 into front and rear is formed.

Further, a tear line 44, which is weaker than other portions of the upper plate portion 36, is formed on the back surface side of the upper plate portion 36 of the cover body 34 by recessing. And this tear line 44
Is a pair of side break lines 45 on both sides formed along the inner side of the mounting wall portion 37, and a center break line 46 as a break portion formed on the back surface side of the central groove 43, It is formed in a substantially H shape in a plane, and by the tear line 44, a pair of front and rear door pieces 48, 48 which are deployed forward and backward when the airbag 25 is inflated
Are sectioned. The central recessed groove 43 and the central broken line 46 are formed at positions displaced rearward from the central portion of the operating portion 41 of the cover body 34 in the front-rear direction. In addition, the wrapping member 31 that covers the airbag 25 also has a fragile tear line.
31a is formed with both sides as the longitudinal direction.

Further, the upper plate portion 36 of the cover body 34 has an operating portion.
A pair of front and rear pressing portions 51, 51 are formed on the back surface side of 41. The pressing portion 51 is composed of a large number of protrusions 52 which are formed in a rectangular shape in a plan view and are provided on the back surface side. The virtual surface connecting the tip-side surfaces of these projections 52 is longitudinally cut along the longitudinal direction. The surface has a straight line shape, and the vertical cross section along both sides has a bilaterally symmetrical arcuate shape, and is formed into a substantially cylindrical surface shape that bulges toward the surface side as a whole.

From the vicinity of the outer periphery of each door piece 48,
Caulking pins 54 for heat caulking are provided so as to protrude toward the back surface side.

Further, as shown in FIGS. 1, 3 and 4, the front and rear membrane switches 32 and 33 are also called membrane switches, and are elastically deformable membrane (film). ing. The front membrane switch 32 and the rear membrane switch 33 have a main body portion that is substantially rectangular in plan view.
55 and a leg piece 56 extending from the main body 55 are formed in a substantially T-shape in the same plane. And
The main body portion 55 is provided with a switch portion 57 having a planar rectangular shape which constitutes a horn switch. This switch part 57
Is provided with a pair of copper foil contacts facing each other up and down, each of these contacts is supported by a support carrier made of polyester film, these contacts are a plurality of spacers arranged at a predetermined interval. Are held in a state of being separated by a predetermined dimension.

Further, a plurality of mounting holes are provided at predetermined intervals along the vicinity of the outer periphery of the switch portion 57 of each of the film switches 32 and 33.
71 are formed, and the caulking pins 54 of the cover body 34 are respectively inserted into these mounting holes 71 to perform heat caulking, so that the switch portions 57 of the film switches 32 and 33 press the back surface side of the cover body 34. It is fixed in parallel along the portion 51.

Further, in this state, as shown in FIG. 5, the switch portion 57 of the membrane switch 33 on the rear side extends beyond the central break line 46 of the tear line 44 to the lower side of the door piece portion 48 on the front side. Is installed and is detachably locked at three locations by the caulking pins 54 of the front door piece 48, and the end of the switch portion 57 of the rear membrane switch 33 and the front membrane switch. The ends of the 32 switch parts 57 are arranged to overlap each other vertically.

On the other hand, the leg pieces 56 of each of the membrane switches 32 and 33.
Is integrally formed with the support carrier of the contact, and is bent downward along the inner surface of the mounting wall portion 37 of the cover body 34. And
A plurality of leg piece attachment holes 72 are formed at the ends of the leg piece portions 56, and these leg piece attachment holes 72 project from the attachment wall portion 37 of the cover body 34 together with the wrapping member 31. It is locked to the provided engagement protrusion 37a and the base plate
It is sandwiched and fixed between the peripheral wall portion 23 of 21 and the mounting wall portion 37 of the cover body 34. Further, a terminal piece 74 electrically connected to one of the upper and lower contacts is projected from the leg piece portion 56, and a lead wire 75 connected to a horn device (not shown) is connected to the terminal piece 74. It is connected. The other of the upper and lower contacts is electrically connected to the boss via the base plate 21, and is electrically connected to the negative terminal of the battery via the steering shaft fitted to the boss. There is.

In the horn switch constructed as described above, when the operating portion 41 of the upper plate portion 36 of the cover body 34 is pressed, the operating portion 41 is bent downward and elastically deformed. Then, by the pressing portion 51 protruding on the back surface side of the operation portion 41,
Each of the film switches 32 and 33 is pressed and bent downward, and the vertically opposed contacts provided on the switch unit 57 are brought into contact with each other to be closed and the horn is blown.

In addition, when a vehicle collides, a signal from a collision diagnosis unit (not shown) is used to output an inflator.
When the igniter of 24 is activated and the filled propellant is burned, nitrogen gas or the like is rapidly injected into the inside of the airbag 25 from the gas injection holes 24b formed on the peripheral surface, and the folded airbag is folded. 25 expands rapidly. Then, due to the inflation pressure of the airbag 25, the wrapping member 31 is split along the tear line 31a, and the cover body 34 is
The upper plate portion 36 is split along the tear line 44. continue,
By tearing the tear line 44, a pair of front and rear door pieces 48, 48 are formed, and as the airbag 25 expands, it expands back and forth at a high speed in a double-door manner to form a protruding port of the airbag 25. Then, the airbag 25 projects from the projecting opening,
It is designed to inflate and deploy in front of the occupant.

When the front and rear door pieces 48, 48 are deployed, the airbag 25 is inflated in the rear membrane switch 33, which is locked by the caulking pin 54 of the front door piece 48. The pressure prevents the caulking pins 54 from being disengaged from the three places and resisting the deployment of the door piece portion 48.

As described above, according to the steering wheel 11 of the present embodiment, by pushing the elastically deformable cover body 34, the cover body 34 and the film-shaped switch 32,
It is possible to operate the horn switch by deforming and closing the switch portion 57 of 33.

Then, the switch portion 57 of the film-shaped switches 32 and 33 attached along the back surface side of the door piece portion 48 of the cover body 34.
Is attached so that at least a part thereof is located on the back surface side of the central break line 46 of the tear line 44, so even if the portion of the tear line 44 of the cover body 34 that is partially deformable is intentionally pushed, Similar to the case where the portion other than the tear line 44 of the cover body 34 is pushed, the switch portion 57 can be easily closed, and the operation feeling of the horn switch can be improved.

Further, the front and rear film switches 32 and 33 attached along the back surface side of each door piece 48 are attached such that the opposite end portions of the switch portion 57 overlap each other. There is no part where the horn switch is hard to ring, including the tear line 44 part of the cover body 34, and the operation feeling when pressing each part of the operation part 41 of the cover body 34 is made uniform and the operation feeling of the horn switch is improved. can do.

Further, as in the above embodiment, the cover body
When the center tear line 46 of the tear line 44 of 34 is formed at a position displaced to the rear side from the center of the operation portion 41, the front and rear membrane switches 32 and 33 having the same shape can be used. Therefore, the manufacturing cost can be reduced by improving the workability and reducing the cost by reducing the number of types of parts.

Although the front and rear membrane switches 32 and 33 have the same shape in the above embodiment, they may have different shapes. Also, in the above example,
Although the switch portion 57 of the rear side membrane switch 33 is arranged so as to exceed the central break line 46 of the tear line 44, the switch portion 57 of the front side membrane switch 33 is arranged at the central break line 46 of the tear line 44.
Alternatively, the switch portions 57 of the front and rear membrane switches 32 and 33 may cross the central break line 46 of the tear line 44, respectively.

For example, as shown in FIG.
For the rear side membrane switch 33 that is mounted beyond the central break line 46 of, the center swaging pin 54 of the front door piece 48
A connecting portion 81 communicating with the outer peripheral side of the membrane switch 33 is formed in the mounting hole 71 for the, and notches 82 and 82 are formed at the corners on both sides, respectively, so that the membrane switch 33 on the rear side is a door on the front side. It may be formed so as not to engage with the crimping pins 54 on both sides of the piece portion 48.

Then, as in the embodiment shown in FIG. 6,
By engaging the rear membrane switch 33 on the opposite side beyond the tear line 44 easily at one place,
While ensuring the operability of the horn switch, it is possible to smoothly deploy the door pieces 33.

Further, in each of the above-mentioned embodiments, the switch portion 57 of the rear side membrane switch 33 is provided with the central break line 46 of the tear line 44.
The switch portion 57 of the rear side membrane switch 33 overlaps with the switch portion 57 of the front side membrane switch 32, but one of the front and rear membrane switches 32, 33 or Both may be arranged so as to cross the central break line 46, and the membrane switches 32 and 33 may be arranged so as not to overlap each other.

For example, as shown in FIG. 7, projecting portions 84 projecting in the form of curved surfaces are alternately extended from the front end portions of the front and rear film switches 32, 33 facing each other, and the respective projecting portions 84 are provided.
The switch parts 57 inside are the tear lines 44 at the center break line.
It is also possible to arrange so as to exceed 46. Then, some or all of these protruding portions 84 are formed with locking groove portions 85 communicating with the outer peripheral side, and these locking groove portions 85 can be detached from the caulking pins 54 of the door piece portions 48 on the opposite sides, respectively. It is locked.

In the embodiment shown in FIG. 7 also, the central break line 46 of the tear line 44 which is easily deformed locally.
Since the switch parts 57 of the film switches 32 and 33 are positioned on the back surface side of the operation part 41, even when the part of the central break line 46 of the operation part 41 of the cover body 34 is pushed, the other parts of the operation part 41 are removed. The horn switch can be closed with the same stroke as when the portion is pushed, and the operation feeling can be improved.

Furthermore, in each of the above embodiments, the cover body 34
And the folded air bag 25 between the membrane switch 32, 33
However, as shown in FIG. 8, for example, as shown in FIG.
The inner body 101 may be disposed between the folded airbag 25 and the airbag body 25, and the switch portion 57 of the membrane switches 32, 33 may be disposed between the inner body 101 and the cover body 34. In addition, the inner body 101 includes a top plate portion 102 and the top plate portion.
From the peripheral wall portion 103 extending downward from the peripheral portion of 102,
Like the cover body 34, the peripheral wall 103 is fixed to the base plate 21, and the fragile tear line 105 is concavely formed in the top plate 102 in a substantially H-shaped plane. In the portion surrounded by the tear line 105, the door piece 106 that is deployed back and forth when the airbag 25 is inflated.
, 106 are sectioned. And the membranous switch 3
2 and 33 are attached to the upper surfaces of the door pieces 106 and 106, respectively, by adhesion or the like, and the film switches 3 and
The projecting portions 84 alternately extending from 2, 33 are located on the back surface side of the central break line 46 of the tear line 44 of the cover body 34, respectively, and the central break line of the operating portion 41 of the cover body 34 is formed.
Even when the portion 46 is pushed, the horn switch can be closed with the same stroke as when pushing the other portion of the operating portion 41, and the operation feeling can be improved.

In the embodiment shown in FIG. 8, the protruding portion is
Although the membrane switches 32 and 33 provided with 84 are used, the membrane switches 32 and 33 in which opposite ends are overlapped with each other may be used as in the membrane switches 32 and 33 shown in FIG. it can.

When the inner body 101 is used,
When the cover body 34 is pushed, by sandwiching the film switches 32 and 33 between the back surface of the cover body 34 and the upper surface of the door piece portions 106 and 106 of the inner body 101, the switch portion 57 is securely closed. It can also be done. In this case, the inner body
The upper surfaces of the door pieces 106, 106 of 101 are formed in a flat shape, and by forming protrusions or ridges of various shapes, stress is concentrated on a part and the switch is operated reliably. be able to. For example, as shown in FIG. 9A, the cross section is formed in a corrugated shape that is bent in an arc, or as shown in FIG. 9B, the cross section is formed in a corrugated shape that is bent in a triangular shape. , Or, as shown in FIG. 9 (c),
It is formed in a wavy shape in which the cross section is bent into a rectangular shape, or as shown in FIG. 9 (d), it is formed with a protrusion 111 or a ridge protruding upward, and further as shown in FIG. 9 (e). like,
The area of the protrusion 111 or the protrusion can be reduced.

Further, in each of the above-mentioned embodiments, the film switches 32 and 33 are heat crimped to the cover body 34 or adhered to the inner body 101. The film switches 32 and 33 can be attached to predetermined positions by adhesion using a tape or the like.

[0041]

According to the airbag device of the first aspect, by pushing the elastically deformable cover body, the switch portion of the membrane switch is deformed together with the cover body, and the switch portion of the membrane switch is deformed. Can be closed. Since the switch part of the film switch attached along the back side of the door part of the cover body is arranged so that at least a part is located on the back side of the break part, the break part of the cover body is pushed. Even when it moves, the switch part can be easily closed and the operational feeling of the switch can be improved, as in the case where the part other than the breakage part of the cover body is pushed.

According to the airbag device of claim 2,
By pushing the elastically deformable cover body, the switch portion of the membrane switch can be deformed together with the cover body, and the switch portion of the membrane switch can be closed. The plurality of film-shaped switches attached along the back surface side of each door piece are arranged in a state where at least some of the switch portions overlap each other, including the portion of the break portion of the cover body, Even if you push any part of the cover body,
It is possible to surely close one of the film switches with a uniform operating force and improve the operational feeling of the switch. When the airbag is inflated, the pressure of the inflation of the airbag causes the cover body to tear along the fragile break portion,
The plurality of door pieces can be deployed to form a protruding port of the airbag, and the airbag can be smoothly inflated and deployed.

[Brief description of drawings]

FIG. 1 is a bottom view of a part of an airbag device of the present invention.

FIG. 2 is a plan view of a steering wheel including the same airbag device.

FIG. 3 is an exploded perspective view of the same airbag device.

FIG. 4 is a perspective view of the same cover body and the membrane switch in an exploded state.

FIG. 5 is a cross-sectional view of a part of the above airbag device.

FIG. 6 is a partial bottom view showing another embodiment of the airbag device of the present invention.

FIG. 7 is a partial bottom view showing still another embodiment of the airbag device of the present invention.

FIG. 8 is a partial perspective view showing still another embodiment of the airbag device of the present invention.

FIG. 9 is an explanatory view showing a partial cross section of another embodiment of the inner body of the airbag device of the present invention.

[Explanation of symbols]

 14 Airbag device 25 Airbags 32, 33 Membrane switch 34 Cover body 46 Central break line as break part 48 Door piece part 57 Switch part

Claims (2)

[Claims] 1. An elastic deformation provided with an airbag which is inflated by the inflow of gas, a fragile rupture portion which covers the airbag and ruptures when the airbag is inflated, and a door piece portion which is deployed by the rupture of the rupture portion. And a membrane switch provided with a switch portion that is attached along the back surface side of the door piece portion of the cover body and that is closed at the time of deformation, the switch portion of the membrane switch being at least An airbag device, wherein a part of the airbag device is disposed on a back surface side of the breakage portion. 2. An air bag that is inflated by the inflow of gas, a fragile rupture portion that covers the air bag and ruptures when the air bag is inflated, and a plurality of door pieces that expand due to the rupture of the rupture portion are provided. An elastically deformable cover body, and a plurality of membrane switches provided with a switch portion that is attached along the back surface side of each of the door pieces and is closed at the time of deformation, the switch portion of each of the membrane switches Is arranged so that at least some of them overlap each other.